English
Related papers

Related papers: AT-algebras from fiberwise essentially minimal zer…

200 papers

We study tensor products of a $C_0 (X)$-algebra $A$ and a $C_0 (Y)$-algebra $B$, and analyse the structure of their minimal tensor product $A \otimes B$ as a $C_0 (X \times Y)$-algebra. We show that when $A$ and $B$ define continuous…

Operator Algebras · Mathematics 2014-02-18 David McConnell

A C*-dynamical system is said to have the ideal separation property if every ideal in the corresponding crossed product arises from an invariant ideal in the C*-algebra. In this paper we characterize this property for unital C*-dynamical…

Operator Algebras · Mathematics 2019-12-19 Matthew Kennedy , Christopher Schafhauser

We recast basic topological concepts underlying differential geometry using the language and tools of noncommutative geometry. This way we characterize principal (free and proper) actions by a density condition in (multiplier) C*-algebras.…

Differential Geometry · Mathematics 2007-05-23 Paul F. Baum , Piotr M. Hajac , Rainer Matthes , Wojciech Szymanski

We introduce the notion of weakly (strongly) infinite real rank for unital $C^{\ast}$-algebras. It is shown that a compact space $X$ is weakly (strongly) infine-dimensional if and only if $C(X)$ has weakly (strongly) infinite real rank.…

General Topology · Mathematics 2007-05-23 A. Chigogidze , V. Valov

Using Kirchberg KK_X-classification of purely infinite, separable, stable, nuclear C*-algebras with finite primitive ideal space, Bentmann showed that filtrated K-theory classifies purely infinite, separable, stable, nuclear C*-algebras…

Operator Algebras · Mathematics 2012-09-14 Sara Arklint , Gunnar Restorff , Efren Ruiz

We define a broad class of crossed product C*-algebras of the form C(G)xG, where G is a discrete countable amenable residually finite group, and G is a profinite completion of G. We show that they are unital separable simple nuclear…

Operator Algebras · Mathematics 2013-01-22 Stefanos Orfanos

We compute the K-theory for C*-algebras naturally associated with rings of integers in number fields. The main ingredient is a duality theorem for arbitrary global fields. It allows us to identify the crossed product arising from affine…

Operator Algebras · Mathematics 2009-06-29 Joachim Cuntz , Xin Li

We show that given a rigid C*-tensor category, there is an equivalence of categories between normalized irreducible Q-systems, also known as connected unitary Frobenius algebra objects, and compact connected W*-algebra objects. Although…

Operator Algebras · Mathematics 2017-07-10 Corey Jones , David Penneys

In this paper, we consider both algebraic crossed products of commutative complex algebras A with the integers under an automorphism of A, and Banach algebra crossed products of commutative C^*-algebras A with the integers under an…

Operator Algebras · Mathematics 2023-05-31 Christian Svensson , Sergei Silvestrov , Marcel de Jeu

We characterise simplicity of twisted C*-algebras of row-finite k-graphs with no sources. We show that each 2-cocycle on a cofinal k-graph determines a canonical second-cohomology class for the periodicity group of the graph. The groupoid…

Operator Algebras · Mathematics 2016-06-28 Alex Kumjian , David Pask , Aidan Sims

We characterize the class of RFD $C^*$-algebras as those containing a dense subset of elements that attain their norm under a finite-dimensional representation. We show further that this subset is the whole space precisely when every…

Operator Algebras · Mathematics 2017-07-10 Kristin Courtney , Tatiana Shulman

Given any unital, finite, classifiable C$^*$-algebra $A$ with real rank zero and any compact simplex bundle with the fibre at zero being homeomorphic to the space of tracial states on $A$, we show that there exists a flow on $A$ realising…

Operator Algebras · Mathematics 2024-11-18 Robert Neagu

We give complete descriptions of the tracial states on both the universal and reduced crossed products of a C*-dynamical system consisting of a unital C*-algebra and a discrete group. In particular, we also answer the question of when the…

Operator Algebras · Mathematics 2021-08-19 Dan Ursu

We construct uncountably many mutually nonisomorphic simple separable stably finite unital exact C$^\ast$-algebras which are not isomorphic to their opposite algebras. In particular, we prove that there are uncountably many possibilities…

Operator Algebras · Mathematics 2024-02-14 N. Christopher Phillips , Maria Grazia Viola

For a fixed C*-algebra A, we consider all noncommutative dynamical systems that can be generated by A. More precisely, an A-dynamical system is a triple (i,B,\alpha) where $\alpha$ is a *-endomorphism of a C*-algebra B, and i: A --> B is…

Operator Algebras · Mathematics 2007-05-23 William Arveson

Certain $*$-semigroups are associated with the universal $C^*$-algebra generated by a partial isometry, which is itself the universal $C^*$-algebra of a $*$-semigroup. A fundamental role for a $*$-structure on a semigroup is emphasized, and…

Operator Algebras · Mathematics 2014-06-03 Berndt Brenken

We show that a bounded, linear map between C*-algebras is a weighted $\ast$-homomorphism (the central compression of a $\ast$-homomorphism) if and only if it preserves zero-products, range-orthogonality, and domain-orthogonality. It follows…

Operator Algebras · Mathematics 2022-04-01 Eusebio Gardella , Hannes Thiel

We introduce the notion of a Tsirelson pair of C*-algebras, which is a pair of C*-algebras for which the space of quantum strategies obtained by using states on the minimal tensor product of the pair and the space of quantum strategies…

Operator Algebras · Mathematics 2022-11-17 Isaac Goldbring , Bradd Hart

We show that a tensor product among representation of certain C$^{*}$-algebras induces a bialgebra. Let $\tilde{{\cal O}}_{*}$ be the smallest unitization of the direct sum of Cuntz algebras \[{\cal O}_{*}\equiv {\bf C}\oplus {\cal…

Operator Algebras · Mathematics 2007-05-23 Katsunori Kawamura

In the present paper we prove a duality theory for compact groups in the case when the C*-algebra A, the fixed point algebra of the corresponding Hilbert C*-system (F,G), has a nontrivial center Z and the relative commutant satisfies the…

Operator Algebras · Mathematics 2007-05-23 Hellmut Baumgärtel , Fernando Lledó
‹ Prev 1 4 5 6 7 8 10 Next ›